14 Of Simple Earths. 5. Tt decompofes the folutions of common gypfum, and ot nitrated or moriated calx. 6. Vitriolic acid dropped into this lime-water immediately forms a vilible precipitate, which lt does not in common lime-warer. 7. This lime-water has ailb the lingular pro- perty, of affording, when faturated, comprefled rhomboidal cryftals, which are nothing elfe but pure lime. 8. lts folution, in the nitrous or marine acids, may be rendered fo faturate as not to difcolour litmus; vvhereas the folutions of barytes in thofc acids have always an excefs of acid. Jargonic Earth *, or Jargonia. This earth hath been difcovered by Mr. Klaproth; it has as yet been found only in the ftone called Jargon, or Circon, of Ceylon, of which rnore hereafter. Ihis earth refembles argill more than any other earth, though it dilfers effentiaily from it in fome refpedts. Its colour is white, and its fpecific gravity probably exceeds 4,000. 1. It is incapable of uniting to fixed air; at leaft, whtn precipitated from acids by mild alkalis, it takes up none. 2. It is foluble in dilute vitriolic acid (as alfo in the nitrous and marine); and with a flight excefs of this acid it forms, in a moderate heat, by ipop ‘aneous evaporation, flelliform cryftals of an allringent tafle, eafily foluble in water. Its * 3 Berl. Beobacht. 147, 6 folu-